Cutter-head



C. P. SMITH. DECD.-

A. L. JONES, ADMINISTRATOR- c ImR HEAD. I,4:OO,245. APPLICATION FILEDNOV. 5, 1919. 1 11 12 3 I I l .9 I I I I,

I I i 12 I (ID I 1 L? 7 I I I I I I I L I I I I I f I I I I I 10 I I I I'I -5 I I I'| I I UNITED STATES PATENT OFFICE.

CHRISTIAN P. SMITH, OF SOUTH BEND, INDIANA; ARTHUR I). JONESADMINISTRATOR OF SAID CHRISTIAN 1. SMITH, DECEASED.

' CUTTER-HEAD.

To all whom it may concern Be it known that I, CHRISTIAN P. SMITH, acitizen of the United States, residing at South Bend, in the county ofSt. Joseph and State of Indiana, have invented certain new and usefulimprovements in Cutter-Heads, of which the following is a specification.

The invention relates to a cutter head for wood working machinery, suchas shapers and planers, and has for its object the provi sion of meansdesigned for more securely holding the cutting knives upon the.supporting cutter heads. Another object resides in the provision ofmeans for holding or clamping the knives to the cutter head in a mannerwhichpermits a greater portionof the knife blades, as they are worn awayin the sharpening process,- to be used and effectively held to place,thus prolonging the usefulness of the knives materially over the type ofcutter heads and knife clamping means as now generally employed, wherebya considerable saving in'the cost of replacements of the relativelyexpensive cutting knives is effected. Still another objectresides in theprovision of a clamping means for holding the cutting knife to thecutter head, which will function to exert a tremendous pressure upon thecutting edge of the knife, and thus prevent shavings and splinters fromworking in between the knife blade and the cutter head, and acting as awedge with a tendency to force said members apart.

With the foregoing and other objects in view, the invention in thepreferred form of details will be described in the followingspecification, reference being had particularly to the accompanyingdrawings, in which Figure 1 is an end elevation, partly in section, of acutter head embodying the improvement.

Fig. 2 is a top or plan view thereof, with the cutter head in theposition shown in Fig. 1.

As appears in the drawings, the cutter head 3 is of the usual form,being provided with T-form slots 4 extending the full length thereof,and outwardly extending lip portions 5 at diagonal corners thereof, thetype shown being adapted for the reception of two cutting knives.Inasmuch as the knives and the securing means therefor are identical, ashowing of one and description thereof is deemed sufiicient for allpractical purposes.

Specification of Letters Iatent. Pate ted D 13 1921 Application filed.November 5, 1919.

Serial No. 335,969.

Adapted to be mounted upon the cutter head 3 is a knife blade 6, havinga cutting edge 7, and preferably two or more slots 8 open toward therear edge of the blade, whereby the blade may be adjusted in effectiveposition, as the cutting edge thereof becomes worn away in thesharpening process, with respect to clamping bolts 9 which pass throughsaid slots. Adapted to bear upon the knife blade is what may be termed aclamp ng bar 10, apertured to permit the clamping bolts to passtherethrough, and which bar is of flexible metal, but flexible onlyunder great stress. Threaded through the clamping bar at the endopposite the cutting edge of the knife blade, are screw members 11,preferably corresponding in num ber with the clamping bolts, andprovided with slots 12 for the reception of a screw driver or othersuitable tool for manipulating the same. The cutter head is providedwith an aperture 13 for the reception of a spindle or shaft (not shown)for revolving the cutter head'at a high rate of speed, as in the mannerand for the purpose wellunderstood in the art.

As will be apparent from the drawings, the head ends of the bolts 9 areheld in the slots 4 in a manner to anchor the same against movementradially of the axis of thecutter head, while at the same timeadjustment thereof may be had lengthwise of the cutter head, whicharrangement permits the ready removal of the bolts from the head forreplacement or other purposes, and permits adjustment thereof so as tocoincide with different spacings between the apertures or slots indifierent knife blades.

The method of manipulating the improved knife clamping means is asfollows: The knife edge is'first adjusted with respect to the edge-ofthe cutter head, and the clamping bar applied thereon, with the screwmembers 11 in position to permit the clamping bar to be drawn as tightas possible upon the knife blade by manipulation of the clamping bolts,whereupon the screw members are turned to force the clamping bar endremote from the cutting edge of the knife away from the cutter head,which action flexes the clamping bar and brings the end thereof bearingupon the knife blade under still greater stress. In such position of theclamping blade, and with the nuts 14 on the clamping bolts serving as afulcrum,

great pressure will. be exerted upon the knife blade adjoining itscutting edge, so'

. of the Clamping bar may first be raised away i from the knife blade bythe screw members 11, and the bolts 14 then drawn home, with the effectto flex the clamping bar in the same manner and with the same results asfirst explained; In additionto the advan-' tages already pointedout bythe flexing of the clamping bar, the same exerts a constant and powerfultension a ainst the underside.

of the clamping nuts, thus serving as an efiective nut lock, which,considering the highjspeed at which cutter heads are revolved and thedanger which may result from'any of the parts becoming loose ordisplaced, is of first importance.

While the foregoing is the preferred form of my invention, it is to beunderstood that I do not limit myself to the precise structure shown anddescribed, as it is obvious that same may be variously modified withoutdeparting from the spirit of the invention. 1' i What is claimed is "1.,Theicombination with a cutter head having a flatjknife blade receivingsurface for the reception of a knife blade, ofa flexible clamping barhaving its under face flat and its rear'edge extending beyond the rearedge of the knife blade and disposed on said knife blade, a holding downbolt carried by the cutter head and spaced'from its edges and passingthrough a notch the knife blade and through an aperture 1n the flexiblebar at a point spaced from its edges.

and an adjusting screw threaded through the flexible clampingbar'adjacent its rear edge and rearwardly disposed in relation to theholding down bolt and forming means whereby .the pressure of theflexible clamp- "ing baron the knife blade may be varied from a pointadjacent the holding down bolt to its forward edge. W V

2; The combination with a cutter head having a flat knife bladereceiving surface for the reception of aiknife blade, ofa flexibleclamping bar having its under face flat and its rear edge extendingbeyondthe rear edge of the knife blade and disposed on said knife blade,holding down bolts carried by the cutter head and spaced from its edgesand passing throughnotches in the knife blade and through aperturesinthe flexible clamping bar at. points spaced from each other and spacedfrom its edges, "and adjusting screws threaded through the flex bleclamping bar adjacent itsrear edge and rearwardly disposed inrelation'to the holding down bolts and forming means whereby thepressure of the flexible clamping bar on the knife may be varied from apoint adjacent the holding down bolts to its forward edge.

ter heads, said device comprising a holding down bolt carried bythe-cutter head and spaced from its edge, the face of the cutter headbeing flat for the receptionof a cutter blade, a clamping bar disposedon the cutter blade and provided With an aperture for the receptionofthe'holding downboit,'a nut threaded onthe holding down; bolt,

3... L knife blade securing device for cut means for flexing upwardlythe rear, side of the clamping bar for increasing the pres sure onthecutter knife from cent the holdingjdown: bolt to its forward edge. V

a point adjain testimony Whereofl my signature.

CHRISTIAN P. SMITH.

